Tetramethylthiuram monosulfide를 ionophore로 이용한 납 이온 선택성 poly(aniline) 고체 접촉 전극

Lead Ion Selective Solid Contact Electrode based on Tetramethylthiuram monosulfide ionophore

Lead (II) ion selective poly(aniline) solid contact electrode based on Tetramethylthiuram monosulfide ionophore as a sulfur containing sensing material is successfully developed. The electrode exhibits good linear response of 25.6 mV / decade (at 20 ± 0.2℃, r2 =0.995) within the concentration range of 1.0 × 10-1 ~ 4.0 × 10-7 M Pb (II). The composition of this electrode was Ionophore : PVC : dioctylphthalate : potassiumtetrakis(4-chlorophenyl)borate : Oleic acid = 5.0 : 20.0 : 25.0 : 4.0 : 5.0. When we consider the results of using different composition electrodes based on only one potassiumtetrakis(4-chlorophenyl)borate or Oleic acid liphophlic additive, poly(aniline) solid contact electrode based on Tetramethylthiuram monosulfide ionophore with potassiumtetrakis(4-chlorophenyl)borate and Oleic acid liphophlic additive had the best result in response characteristics. The electrode shows good selectivity for lead (II) ion in comparison with alkali, alkaline earth, transition and heavy metal ions. This electrode is suitable for use with aqueous solutions of pH 3.0 ~ 7.0 and their standard deviation in the measured emf differences was ± 2.94 mV at Tris buffered lead sample solution of 1.0 × 10-2 M and ± 2.82 mV at Tris buffered lead sample solution of 1.0 × 10-3 M. Their stabilization time was less than 710 s. and response time was less than 16 s.